Deep seismic investigations in the western part of the Rhenish Massif, Rhenohercynian
The European Variscides, extending from the French Central Massif to the East European Platform, originated during the collision between Gondwana and Baltica in the Late Palaeozoic. Due to involvement of various crustal blocks in the orogenesis, the mountain belt is subdivided into distinct zones. The external fold-and-thrust belts of the Rhenohercynian (RH) and Saxothuringian (ST) as well as the predominantly crystalline body of the Moldanubian (MN) dominate the central European segment of the Variscides. Polyphase tectonic deformation, magmatism and metamorphic processes led to a complex interlinking between the units.
The campaign DEKORP 1 was carried out in the Rhenohercynian zone, a foreland fold-and-thrust belt cropping out in the Rhenish Massif. Extending from the Ardennes to the Harz Mountains it consists predominantly of Devonian and Lower Carboniferous rocks. DEKORP 1 consists of 3 seismic profiles crossing the Variscan structures of the western Rhenish Massif almost perpendicularly.
DEKORP 1 aimed
- to investigate the crustal structure of the western part of the Rhenish Massif,
- to relate these structures with results of DEKORP 2N, carried out east of the Rhine River.
DEKORP 1 was a joint reflection venture with the BELCORP group (Belgian Continental Reflection Seismic Program) of the Belgian Geological Survey. The seismic survey was carried out in 1987 and consists of the 3 seismic lines DEKORP 1A, 1B and 1C with a total length of 220 km (see location map).
Experiments
DEKORP 1A:
The 93 km long, WNW-ESE trending DEKORP 1A line crosses the Variscan foreland in Belgium, the northern Variscan Deformation Front (Aachen Thrust) and the Stavelot-Venn Anticline, arcing around the depression of the Eifel Nord-Süd Zone.
DEKORP 1B:
The nearly N-S trending DEKORP 1B line has a length of 50 km and intersects DEKORP 1A near the city Adenau. It crosses the western volcanic zone of the Eifel, the magnetic "Kelberg High" as well as the Siegen Main Thrust and ends in the Mosel Syncline.
DEKORP 1C:
Merging with line 1B, line 1C starts in the Mosel syncline and trends WNW-ESE into the Permian Saar-Nahe basin. Its total length is 75 km. The seismic profile crosses the Devonian Hunsrück slate belt with its southern metamorphic zone as well as the complex Hunsrück boundary fault, separating Rhenohercynian and Saxothuringian. The end of line 1C merges with DEKORP profile DEKORP 9N running across the northern part of the Upper Rhine Graben.
long (start) lat (start) long (end) lat (end)
DEKORP 1A 5.88062 50.76737 6.98251 50.35353
DEKORP 1B 6.88279 50.42300 7.05623 49.98625
DEKORP 1C 6.99157 50.04135 7.79118 49.62337
